How do you bake out a world space/position normal maps?
An object-space normal map, on an object without any rotation or parents, is also a world-space normal map.  So you can just unparent, clear rotation, and bake an object space normal map if you want world-space normals.
When I want to output arbitrary data, I generally use emission.  Run geometry/position into emission for world space position.  Remember that position is in Blender units-- save to .exr (which supports floating point values) if it goes outside of 0,1 range, or remap.
If you want some other way to bake world space normals, consider remapping the channels of geometry/normal from -1,1 range to 0,1 range, then emitting and baking.  Unless your application expects them in the -1,1 range, in which case, don't remap them, just remember to save as an .exr to support the negative numbers.
Whenever you're baking any values like this, remember that you want to bake to non-color data: